Principle of operation
Although the device does not actually work without being connected to the electrical network (compressors are powered by electricity), the liquid rise
It is carried out only due to the action of a physical law that regulates the movement of water in communicating vessels.
Due to aeration (saturation of the liquid with air bubbles), the water at the end of the tubes becomes lighter and weightless, carbonated. Air bubbles rush upward, carrying water and silt particles with them - this ensures simple and reliable transport of sewage contents between the working compartments of septic tanks or biological treatment plants.
To free water from excess gas, it is passed through separators - umbrella-type devices that remove air.
How to choose
The main task of airlifts, performed in septic tanks, is the movement of wastewater from the receiving compartment to the aeration chamber (aerotank) inhabited by bacteria. In this operation, the speed of execution is most important. The faster the receiver is released, the less likely it is that fermentation and the appearance of an unpleasant odor in the area near the sewer. In the aerotank, odors are quickly destroyed due to the coordinated work of aerobic bacteria - the liquid decomposes into environmentally friendly sludge and water.
If this node fails, it can be replaced with both a universal model (suitable for most septic devices) and a certified device (manufactured by the manufacturer for a specific brand of septic tank).
The main factors that serve as a guide when buying are:
- the performance of the device (it is checked against the performance of the septic tank itself, indicated in the technical data sheet - this indicator cannot be lower than recommended!);
- quality - you need to buy only certified products from a trusted supplier of spare parts and septic tanks.
Is it possible to make an airlift with your own hands
Making airlifts with your own hands for the further use of this home-made device in a septic tank with an aerator,
ensuring the vital activity of aerobic bacteria is more theoretical than practical.
Basically, the owners are trying to use industrial models of septic devices and accessories for them. Or they build self-made structures with a separate aeration chamber, in which there is no classic airlift. Instead, a sealed metal tube with multiple perforations is installed, which ensures the mixing of the contents of the chamber and its decomposition into sediment and purified (clarified) water.
Homemade airlift looks a little different. By connecting two plastic pipes, into one of which the compressor pumps compressed air, you can get the desired simple pump for lifting any liquid.
However, the whole secret of such an installation lies in the exact selection of the diameter of the working pipes and its ratio to the height (depth of immersion).
For each diameter, there is an optimal ratio of lifting height and immersion depth. Having made a mistake in the calculations, you can end up with a non-working airlift. And the task of the engineer in this case lies precisely in achieving the maximum value of efficiency!
The basic calculation formula is: the immersion depth should be divided by the sum of the same depth and the liquid rise height. With a value of 0.7, the maximum possible efficiency will be achieved for a given volume of the tube that lifts liquid or suspension (transporting it outside the septic tank receiver chamber).
It should be noted that:
- If the depth of immersion does not greatly exceed the height of the ascent, then the efficiency will be within 30%.
- The larger the diameter, the greater the amount of liquid can be raised per unit time (the supply will go in batches - the water in the tube alternates with air pockets).But with an increase in diameter, a large air supply to the system is required, that is, a more powerful and less economical compressor is needed.
System calculation principles
A homemade airlift will perform its functions, subject to the correct calculation of the main characteristics. To equip the system, you need to know the following parameters:
- The water level in the well is described by 2 main quantities: the static level (H1) is the depth of the upper boundary of the water before the airlift works, and the dynamic level (H) is the depth to the water after the system is started.
- Depth of immersion of the air supply pipe. It consists of H and the depth of immersion in the water column (h), that is, H + h.
These parameters determine the choice of pressure to be provided by the compressor.
In addition to the specified parameters, it is impossible to determine the performance of the installation without specifying some dimensions of the structural elements.
The following values are important: the diameter of the well casing string Ds, the diameter of the water-lifting pipe J and the diameter of the air duct Dv. These dimensions are interconnected and determine the volume of water raised (Vv)
So, with Ds up to 100 mm, Vs within 1-2 l / s is provided at J - 40 mm and Dv - 12 mm, and Vs is about 3 l / s at J - 50 mm and Dv - 13-20 mm. The increase in productivity occurs with large well sizes, which makes it possible to use pipes of a larger diameter. For example, Vs of the order of 9-12 l / s at Ds - up to 200 mm is achieved at J - 85-90 mm and Dv - 14-30 mm, and 22-32 l / s at Ds - 250 mm, J - 120-126 mm, Dv - 40-50 mm.
The immersion depth h is directly related to the total height of the water rise. So, at a lifting height of up to 15 m, the ratio 100h/(h + H) is chosen to be about 67-72%; in the range of 16-30 m - 60-65%; 30-60 m - 50-59%; 60-90 m - 44-49%.
In addition, the ratio h/H determines the efficiency of the airlift. The maximum value of the coefficient (about 37.8%) can be expected at h / H - 2.2-2.25. At h/H=8.7 efficiency is minimal (within 26.4-26.6%).
The pressure at the beginning of the compressor operation is determined by the static level, that is, the height of the water column, equal to H1, and during operation it can be reduced to a value corresponding to the dynamic level H. At the same time, the H level is always significantly lower than the H1 level.
Another parameter that needs to be determined when designing a system is the required air volume (Vv). It is customary to calculate it in the form: a cubic meter of air for every cubic meter of water raised. The calculation is carried out according to the formula: Vv \u003d H / Сlg0.1 (h + 10), where C is the tabular coefficient associated with the magnitude of the pipe immersion (has a value from 8.4 to 14.3 when the immersion changes from 35 to 75%).
Do-it-yourself sewerage for a country house
Modern economic conditions have led to the fact that the owners of country houses and cottages, preferring to save money, try to do the maximum work in the house with their own hands.
Of course, not all works are available without special knowledge and appropriate training, but it is quite possible to install a septic tank (sewerage) yourself. All you need is physical strength.
First you need to determine which sewer components should be purchased. It is necessary to decide which sewage system will be good for your site and your country house.
The main types of sewerage
- The first type, the simplest and most ancient, is an ordinary cesspool. Everyone knows her.
- The second sewage option is a system consisting of overflow concrete wells. The disadvantage of such a system is that it will have to shovel the entire area and periodically call a car with vacuum trucks, which will require appropriate access roads.
- The third sewage option for a country house is a septic tank, which can be plastic or fiberglass. During its installation, filtration fields are provided, which eventually become silted up and begin to emit an unpleasant odor. In addition, for such a sewer, it is also necessary to call an ilosos (a sewage truck with a hose) from time to time, which means that access roads are also required.
- The fourth, and perhaps the best option for a separate sewerage of a private house, is a station that performs deep biological treatment. A special technology upgraded to Russian conditions, where land and climate features are taken into account.In addition to its technological advantages, the aeration station is extremely easy to install.
Therefore, if you have chosen the best option, that is, an aeration station, then you can start the installation yourself. Depending on how high the groundwater is and the permeability of the soil, a station with a gravity outlet for sewage or a station with a forced discharge of purified water can be installed.
If the groundwater is low, then the best option would be a gravity-flow option, for which you can use the drainage available on the site. When the groundwater level is high, treated water is pumped into an adjacent drainage ditch.
Installation of aeration station
The first step before installing a cleaning station is to dig a pit, the minimum dimensions of which will be 1.5 x 1.5 x 2.3 meters
A station should be installed in the pit, paying attention to the fact that the receiving chamber goes directly to the sewer pipe.
The second stage will be the installation of the station in the pit. Small stations, designed for one to one and a half cubic meters per day, are made of lightweight polypropylene (foamed plastic)
Therefore, three or four people will be needed to lower the station into the pit. The station is set horizontally, strictly according to the level, and then filled with water to the marks made inside. At the same time, sand is sprinkled, which is poured with water for density. However, you should not fall asleep completely, as drains will be brought later.
The third stage of the installation of the station includes digging trenches, which will contain inlet (110mm) and outlet (50 or 110mm) pipes. The inlet drains must be laid with a slope of 2% (2 cm of slope per 1 m of length). To connect them to the station, you need to drill the appropriate hole and solder the pipe using an industrial hair dryer. For a gravity station, you don’t need to drill anything, there is a stationary exit. For a station with forced ejection, a special hole is drilled for a hose with a diameter of 32 mm.
The fourth stage consists of supplying electricity to the station. It is necessary to use a cable of the PVS 3 * 1.5 brand, which must be threaded into a plastic pipe or corrugation and laid in a trench.
As you can see, installing a sewer with your own hands is not at all complicated.
The main thing is to choose a sewer and purchase the necessary components.
1 How aeration works
The aeration process allows you to purify water from the following harmful impurities:
Purification of water from these elements occurs as a result of the oxidation reaction of molecules and their transition from a soluble to an insoluble form, which, in fact, are ordinary mechanical particles deposited on filter devices.
The aeration process itself cannot be the only stage in water treatment, but it is a necessary condition, without which high-quality water filtration cannot be performed.
Today, a large number of methods for oxidizing and preparing water for filtration are available, but most of them have a number of significant drawbacks in the form of the cost of the process, or in its inconsistency with environmental standards, while aeration fully satisfies all the basic requirements of high-quality industrial water treatment.
An example of the application of the aeration method for an open reservoir.
- Safety: no third-party chemicals are added to the water that can harm the human body;
- The cost of the aeration process, in comparison with methods that give an identical result, is quite low: financial costs are required only for the purchase of equipment, and for the subsequent payment of electricity for the operation of the machines;
- iron removal by aeration can be carried out for large volumes of liquid at the same time;
- Improving the taste of water due to its enrichment with oxygen;
- Possibility of full automation of work;
- Environmentally friendly: since aeration does not involve the use of any chemicals, there is no chemical waste at the end of the process that needs to be disposed of somehow.
The only significant drawback of aeration is the need to use bulky equipment, which somewhat complicates its domestic use.
However, there are types of aeration that involve very compact devices that are great for home use. Moreover, with the right approach, the simplest aeration of water can well be done on do-it-yourself equipment.
Compact submersible aerator.
